So many of you emailed me with questions that I put together a Q&A. This is a far broader topic than I can summarize (even with six hours of writing!), but it’s a start. The formatting is ugly and you’ll have to scroll through a lot of text. I’m prioritizing your access to the information over making it look nice. Expect typos.

I don’t have allergies. Could I still have an issue with histamine?

Absolutely. I don’t have allergies either and have no allergy symptoms. Right now, I can only present myself as a case study and say that I’ve encountered multiple people in forums who are histamine-intolerant and do not have allergy symptoms. This is on my list of topics to investigate and I’ll present real data when I can.

What’s the name of the supplement you use and where can I buy it?

The actual name is Histamine Block and it’s available on Amazon. Histame is probably the most popular DAO supplement. It costs less than Histamine Block, but is also less potent. (I’m an Amazon affiliate, so I’ll get a small portion of the sales if you purchase through one of those links. I have no relationship, financial or otherwise, with any company that manufactures or sells DAO.)

What is an HDU?

HDU stands for “histamine digesting unit” and you’ll see it listed on every DAO supplement. It appears to be a scientific term that’s been co-opted for marketing, but the two don’t align. Currently, I only use the numbers to compare the strength of one supplement to another. I’ve also found that, so far, 20,000 HDU is most effective for me.

I don’t get a migraine or headache every time I eat, but I do sometimes and can’t connect it to any particular food. Could DAO help me?

Quite possibly. I think I’m fairly rare to have eating anything trigger migraines (or histamine intolerance symptoms). Far more common is for people to have trouble with particular foods. Certain foods naturally contain histamine or are “histamine liberators,” both of which result in even higher amounts of histamine to your system than is part of the normal digestion process. Most people don’t have as much trouble with the normal histamine release as I do, but run into problems when they eat foods that contain or liberate additional histamine.

What foods contain or liberate histamine?

This is a landmine. The short answer is that you will find many conflicting lists of histamine-containing foods online. Searching forums will confuse you even more. Here’s the list of histamine-containing foods that’s most widely regarded as accurate. You’ll notice that it also includes foods containing tyramine. The two are related (both being amines) and there’s a lot of overlap between them. Tyramine has long been suspected to trigger migraines, and possibly other headaches, so a list restricting both is a good place to start.

Starting an elimination diet is overwhelming and time-consuming and I have tons of guidance to offer. On another day.

Will DAO work if I don’t change my diet?

Maybe, but the odds are against you. Here’s a full post on DAO and diet. lAdded Dec. 3, 2014]

Are DAO supplements safe?

Yes, according to the dietician I’ve been consulting with (who is as close to an expert on this topic as you can get), my naturopath, and the recent DAO for migraine prevention study. Any of the DAO that isn’t used is flushed out through the digestive process. It’s not absorbed in any way, nor does it stick around for more than a few hours. (The information in the last two sentences is from my naturopath. I’m going to double-check it with the dietician.)

Do DAO supplements have any side effects?

None of the 117 patients who completed the aforementioned study of DAO for migraine prevention reported any side effects. That’s pretty much unheard of for a study of a drug or supplement. Online forums are a little different (and also not part of a controlled experiment).

The main side effect I’ve seen on forums is that some people say it makes them shaky. That was true for me initially. Taking the DAO only five minutes before I ate seemed to help, I think because it didn’t sit in my stomach for too long without food. I did that a few times before moving to taking it 10 minutes before eating. My intuition is that it is more effective if it has more time to release before encountering food, but I don’t know that for sure. I’ll ask my dietician about it.

Someone just told me that she flushes and sweats when she uses any brand of DAO supplement. That’s the first time I’ve heard of that side effect and I don’t know how common it is.

I sometimes react to natural supplements. Am I likely to react to this one?

I’ve demonstrated so much intolerance for natural supplements that my naturopath only prescribes pharmaceuticals for me(!), but I’m doing fine with this one. Use your own judgment to decide if the risk is worth it for you. If your reactions tend to be severe or you think the risk is too great, consulting with a naturopath or dietician before taking it would be wise.

Where did you learn about DAO supplements?

The dietician and my naturopath both recommend it. It is also commonly used among people with histamine intolerance, so it’s mentioned on forums a lot.

If I have a histamine issue, could I take antihistamines instead?

If your triggers are connected to food or eating, it appears to be more effective to take DAO than an antihistamine. Adding the enzyme you’re deficient in seems to address the problem more directly than an antihistamine. Antihistamines can also cause a strong enough rebound effect that the dietician warns against them. For now, I’m still taking 12 mg of cyproheptadine, a prescription antihistamine used for migraine prevention, each day.

If you do decide to try an antihistamine, patients with histamine intolerance (whether their symptoms are migraine, headache or something else) seem to have more success with older drugs, like cyproheptadine and Benadryl, rather than the newer ones (Allegra, Claritin and Zyrtec). I don’t know why.

What’s “histamine intolerance”?

Histamine intolerance (often referred to as HIT) is when someone has a reaction to ingesting histamine and/or the release of histamine that accompanies digestion. The reactions vary, but can include diarrhea, headache (and migraine) nasal congestion, wheezing, low blood pressure, irregular heart beats, rashes, flushing, and itching.

Histamine intolerance isn’t a food allergy, but is a food sensitivity (it’s an important distinction). It’s not widely known about, but is starting to get a lot of attention in parts of Europe (especially the U.K.) and Australia. Thanks to the internet, the information is accessible if you know where to look.

For what it’s worth, I haven’t been diagnosed with histamine intolerance, nor have I diagnosed myself with it. But it’s the best search term to find information on histamine and food, and it’s the term most people who have issues with histamine apply to themselves.

Why do you qualify so many statements with “appears to” and “seems to”?

There are a lot of unknowns about histamine and DAO. Finding solid information online is difficult and patient groups lean toward pseudoscience. While I believe I’ve sussed out reliable information, I would rather say I’m not absolutely sure about something than discover that I presented incorrect answers as fact. If I continue to feel as good as I have this past week, I’ll soon be combing through journal articles at the local university library and will pass on what I uncover.

What else do I need to know?

I’m sure I’ll be sharing much more as the week — and year — goes on. If you want to know more NOW (I sure did when I first started learning about this), here are some places to get started:

Histamine Intolerance Awareness (website) — The food list on this site is kind of difficult to follow and some of the inclusions are questionable, but the rest of the information is a very helpful start. Genny Masterman, who put this site together, has a book called What HIT Me? It’s a good introduction and is written in an accessible, easy-to-follow style, but I found the meatiest information to be covered sufficiently on the website.

Dealing with Food Allergies (book) — This is my favorite book for the general public, even though the title is misleading (histamine intolerance is NOT an allergy). It doesn’t contain a lot of detail, but hits all the important points and has clear, well-organized food lists. Be sure to check the sections on both histamine and benzoates (benzoates are histamine liberators). I think there’s a section on tyramine as well. The author, Dr. Janice Joneja, the dietician I’ve been working with.

Histamine and Histamine Intolerance (journal article) — If you’re willing to wade through an academic article, this is the one to read. I’m working on summarizing it, but not sure when it will be ready to post.

Other websites — If you come across another website and are wondering how accurate it is, please ask me. I’d like to have multiple sites to refer people to and it would be helpful to see which sites people who are new to this topic find.

Please remember that I’m not a medical professional and nothing on this site should be considered medical advice. I’m a patient reporting on what I’ve learned and experienced. I hope that it can help you with your own sleuthing, but please solicit the input of your health care team.

Thanks so much for this. I have one question, though. Why is Histamine Block more effective than Histame? I looked at both of them, but cannot take Histamine Block because it uses an Ascorbic Acid Vitamin C base (I cannot take this due to a food sensitivity problem I have for another condition – nterstitial cystitis)

Gail, Histamine Block is more effective for _me_ because it is a higher dose (10,000 HDU per capsule vs. 4,000 in Histame). Some people get all the benefit they need from one Histame. You can take multiple Histame capsules, if necessary, though that would be more expensive than Histamine Block.

I started with Histame and took more and more capsules to get to the dose I needed. Histame costs about $.80 per capsule, while Histamine Block is about $1. And it takes five Histame to equal the dose in two Histamine Block.

I have had migraines for 30 years. I thought that after going through menopause they would subside (ten yrs ago) they only increased. I use triptans to fight them, allot of triptans. Here in Ireland you can get them at minimum cost for in our drug scheme. That is still €140 per month but better than the States which is where I am from. Anyway I stopped all caffiene consumption two weeks ago. It was a horrible withdrawal which should tell me something aobut its effect on me. I have also started to eliminate all foods with tryasine. I just saw your article here today and will also include those with histimine. The feeling I always had with my migraine is that they felt like horrible hangovers. Throwing up and all. I feel great without the caffiene and hopefully simplifiying my diet will help enormously. Then maybe I’ll only have to use the triptan once in awhile. Wouldn’t that be wonderful. I also just dicovered the tea Rooibos..had never heard of it before. Its great for replacing the coffee. Thanks for all your time creating this website. Cheers.

Hi Patty.
Your story is very similar to mine. I have daily chronic migraines and have been constantly researching hoping to find new answers. I’ve always had the premenstral migraine, but the daily migraines started in my early forties and I am now 55 and I am still getting them almost daily. As like you, I was hoping once I reached menopause, they would stop, but unfortunately they didn’t. I take 1-2 Zomig ( prescription ) a day combined with 2 Tylenol and I get Therapeutic Botox injections every three months. This is the only regime that makes them tolerable. I just recently came across an article on histamine intolerance. It said that approximately 87% of migraine suffers lack the enzyme that breaks down histamine in the gut. The researchers explained that having too much histamine causes our blood vessels to dilate triggering migraines. It also talked about eliminating wheat and sugar, as well as foods high in histamines. Basically reducing inflammation in the body. Wheat and sugar are health-sapping inflammatory foods. Another suggestion they made was to take a probiotic inorder to balance our gut bacteria. We want 85% good bacteria and only 15% bad bacteria. Recommended amount was 25-100 billion dairy free capsules daily.
Wishing you all the best and hoping you will be migraine free!!!!!

Thanks for the information, Margie. I want to clarify that histamine’s role in triggering migraine is quite involved and not entirely understood. Blood vessel dilation may or may not be the culprit; more studies need to be done to determine that for sure. Also, some strains of probiotics _produce_ histamine. I’ll work on a post about that. In the meantime, these are strains that are beneficial for DAO production: lactobacillus curvatus, lactobacillus sakei, weisella hellenica, leuconostoc mesenteroides, escherichia faecium sp.group, sarcina lutea. I don’t believe all are readily available.

I just starting with a DAO supplement….do you take yours before EVERY meal or only when you feel an issue with symptoms coming on? Id like a preventive approach v. reactive but wasnt sure if taking the supplement prophylactically would be done with every meal or once or twice a day, etc.

I have been struggling with figuring out my triggers for 2+ years and am thinking that maybe it could be a histamine reaction. Did your doctor/dietician test you for DAO levels before putting you on the supplement? Or did you just try it to see if it would help? Did you also eliminate all the foods indicated on the mastocytosis site?

There is a test for DAO levels, but it is considered unreliable. The level of DAO in a person’s blood may not correspond with the amount available for digestion and there’s no solid range in which to identify what’s normal. Trying a DAO supplement and seeing if it helps provides most people with more evidence than the blood test.

I have eliminated all the foods on the mastocytosis site, but I had eliminated ALL food before starting DAO (literally, I was subsisting on a formula that’s used in feeding tubes). I just haven’t added anything that’s high in histamine back in permanently. I have tried some high histamine foods, but took more DAO than more normal amount beforehand and I did fine.

Thank you for putting this together. There is one thing that not many people with histamine intolerance consider, and I am interested to know if you have heard anything about it. Histamine is produced by a number of bacteria, and I wonder how much of a role gut dysbiosis plays in this, and whether fixing the dysbiosis is key to reducing the drains on the bodies own supply of DAO. For me, my histamine tolerance has changed markedly at a number of points in my life. I have done the GAPS diet in the past and had much better success at handling histamine. Then I got a weird bug last year and not only do I have a strong response to anything containing histamine or tyramine, but I also have the same response to protein, any type of protein, fresh or old, nuts or meat. Except the response is delayed by a number of hours. This makes me wonder whether the bug that caused sores in my mouth, was a bacteria that went through to my gut and produces histamine from histidine. Histame really helps control this, but without it, each time I eat protein, I get all the same symptoms that I used to only get for histamine. Postural hypotension, muscle fatigue (walking up 5 steps – and I am active), tiredness, and all the mood problems like shortness of temper, irritability, brain fog, poor concentration and sound intolerance. I also get a very sharp pain under the upper rim of my left eye socket. This is in the same spot that people get cluster headaches from histamine. So I would like to a) find out more about this theory, and b) raise this question with as many people as possible, to see if others have found a similar pattern in their responses.

Thanks for sharing your experience, Sarah. You’ve raised far more questions than I have answers to. People do find that healing their guts helps with histamine intolerance, though I don’t know exactly how they do it, since GAPS foods are pretty much the antithesis of low-histamine.

How frustrating that you’ve developed a new protein reaction. I don’t know if a virus can impact histamine reactions or impede protein production in some other way. The dietician I consulted is fantastic and does Skye consultations — she may be able to answer your questions. Let me know if you want her name.

Do you have migraine? Your symptoms, including the eye pain, sound very migraine-like. I’m not sure what the protein connection there would be either, but a diagnosis might help you sort things out.

Thank you Kerrie, I am sorry, but I somehow missed your reply. I do know that some people have achieved relief from histamine intolerance from GAPS diet, and I used to before I had that weird bug (I meant a bacterial one) however, it does not succeed for everyone. I don’t think it deals with overgrowth of protein consuming bacteria, rather it deals with carbohydrate feeders. I have considered going very low protein for a while, I have felt really good when I have done this in short stints, but biologically not a sound idea. I have considered only using instantly digestible fresh stock without meat, so no protein carried through into the lower intestines as undigested meats etc. However, at the moment, I am just getting so much relief from Histame that I have lost the drive to go on such a strict diet. I am a little busy as i have decided to get fully into solving this issue and I have started a Bachelor of Med Sci (Nutrition) to further develop my understanding then become a Nutritionist to help others understand it. As we all know it is hard to find professionals that are knowledgeable about this and other food intolerance issues and their causes.

Oh, I forgot, yes I do get Migraine symptoms (visual disturbance and mild headache which can come up to a day later) although they seem different to my eye pain which is instant on consumption of high or moderate histamine. The nearest thing I could find about it considering the location was Histamine induced cluster headaches. There is a little bump under my upper left eye socket rim that goes hard and painful and this is where the pain comes from. Rubbing it like a trigger point seems to make it worse. If anyone can enlighten me to it’s cause or how to get rid of it, I would be very appreciative.

Sarah, how exciting that this has started you on a new career path! The GAPS diet is perilous for a lot of people with histamine intolerance — so many of the foods are high in histamine that it hurts some people more than it helps. Though I do know of people who start benefit from starting GAPS after getting their histamine reactions somewhat under control.

Migraine symptoms can vary from one migraine to the next and even one trigger to the next. Your eye pain could be a different manifestation of migraine. If you truly think you have cluster headache, please see a doctor for diagnosis and treatment. Cluster headaches are viciously painful; you want to get on top of them as soon as possible.

I can’t thank you enough for publishing this information. I have had migraines since the age of 7 and have followed the tyramine diet for the last 20 years but still have debilitating chronic dailies. I am convinced that histamine now is the problem and i will try this. But I also have serious upper gastric pain and nausea and i wonder if you had any problems with this also? (the g.i. doc can’t find anything wrong, go figure?) I am hoping this will disappear once i eliminate the enormous remaining number of foods i have continued to eat all these years???
I will also try a DAO. thanks for helping me, I will let you know what happens.

Nausea and abdominal pain are both migraine symptoms, so whatever helps the migraine could help those symptoms as well. I had nausea intermittently until the migraines got really bad, then it became constant. It’s very rare now for me to have nausea.

HI
I started having problems with my sugar causing several hypoglycemic panic attacks. Now it always feels like my throat it closing. So I have stop smoking thinking that was my problem. That was four months ago and I still feel that way so now I have even stop drinking socially and it had gotten better until recently three weeks ago I drunk two cups of coffee for breakfast and I haven’t been right since. The attacks is back and the headaches and dizziness while working(a fast paced environment) almost feeling like a hypoglycemic attack but that couldn’t be the case because I would have just eaten. So with me taking anxiety meds periodically do you think I may have a bit of histamine problem? Doctors have said my Hmg A1c has been fine. But I still feel am the same symptoms.

Thank you all for sharing your stories. I can relate to each and every one of you. Histamine is also a marker for methylation imbalances that cause many of the symptoms/challenges you list. It took me over 25 years to finally figure this our for myself, but today, I am symptom-free and really love life. You can read more about methylation and epigenetics here: http://samanthagilbert.com/methylation/

Wow so happy to get a mention on this blog! I hope folks stop by my blog and take a look at all the research I’ve done. I haven’t used DAO supplements but have gotten my intolerance under control with careful diet and some common vitamin supplements.

Olive oil, ginger, and vitamin C all help to get histamine under control. Stop by and take a look!

This is confusing Kerrie because the list that you reference made by Dr. Joneja states that Olive OIl and Coconut Oil are both safe for Low Histamine diets. I’m confused. Why do you say that about Olive Oil then? Do histamines release in both raw and cooked state?

Nicky, there are a lot of individualized reactions to foods. It’s one of the super-frustrating things about low-histamine diets. Also, different lists have different foods to avoid. Olive oil is one that quite a few people report having trouble with, but others do just fine with it. I was fine with coconut oil for months, but now have such a reaction to it that I get a migraine if I get even a little on my skin. It could be histamine or it could be some other sensitivity I’ve developed.

Also, would you also recommend not even using a pressure cooker as a replacement to a slow cooker for meats? I was reading about how some people in the AIP community are using pressure cookers instead of slow cookers so that it doesn’t release as many histamines.

Nicky, I got a pressure cooker last summer and use it all the time. It cooks meat very quickly and you don’t even have to defrost frozen meat first. Some people say they believe the high temperature is an issue, but it hasn’t been for me.

I have been researching food intolerance for the last 16 years and have my own private practice as a Physio and Homeopath. I have discovered the 4 main miasms/, flaws that are inherited combine to form 10 distinct profiles of food intoletance and every one inherits one of the ten patterns and they are quite definitive. My theory therefore is that it is those intolerant foods particular to each person that cause the excess histamine reaction. This means that avoiding all histamine rich foofs is not necessary—only those they are sensitive to. However the added complication is the huge contamination in the food chain which is affecting us all adversely. The symptoms and diseases caused by the excess histamine reaction are far more widespread than is realised eg autoimmune diseases etc Therefore DAO could well be a real saviour in disguise. Saying that hundreds of my patients are now well from avoiding the foods they are sensitive to as well ad correcting their nutritional deficiencies.

Hi there,
I’m senstive to histamine and I’m using Daosin, a dietary supplement for almost 3 month. It helps me to eat my favourite food even if it’s histamine rich. No more sorrow 😉 For those who have no idea, if I were you I would try it out and maybe you will like it!

earlier in the message stream you said migraine patients had luck with benedryl and older antihistamines and didn’t know why. The older ones crossed the blood brain barrier, and that is why they make you sleepy like Amitriptyline/Elavil. Zyrtec, Allegra and any advertised “non-drowsy” antihistamines do not cross the BBB. They act only on peripheral tissues which is fine for nasal allergies not so great for migraine! Thanks so much, your blog is saving my daughter much agony.

I am a chronically I’ll Lyme disease with coinfections sufferer along with autoimmune disease, thyroid disease, and hormone and adrenal problems. I’ve noticed most things I eat that make me sick are histamine high foods and I have daily migrsines in which I’ve tried everything. I also have food allergies to wheat barley rice dairy beef pork and may have alpha gal according to my doc. I am geting my toxic load down, taking enzymes, and probiotics. Since you are a chronic migraine sufferer can you tell me your advice on what so should start with. I just want to eat. I can’t eat tomatoes watermelon coffee chilli powder corn and many more things that im not allergic to but give me sinus and migraines. I have a great naturepath and doc that would be onboard for anything to help me. we have been focusing on all my infections and haven’t even addressed histamine yet. my allergy doctor was pretty much unable to help me.

Chastity, food sensitivities can be difficult to sleuth out. Dealing With Food Allergies, a book by Janice Joneja, has some helpful information on tracking them down and testing new foods. She recommended to me that I avoid foods high in histamine and tyramine, which has been helpful. I’ve found some success with a rotation diet: http://www.thedailyheadache.com/2014/07/rotation-diet-migraine-headaches.html. I only have 40 foods in my diet right now, which breaks down to 10 different things I can eat on any given day. It’s restrictive, but way better than having to drink feeding tube formula! I with you all the best in getting this sorted out.

When I was tested for allergies the reaction the histamine gave me was flushing in the extreme and I felt ill. The Allergie Doctor said that he had only seen the depth of reaction a couple of times. My PCP also told me that he was was allergic to histamine. It is getting worse as time goes bye…I have been put on Januvia (50) mg for about three months. Could the medicine cause the flushing to get this extreme. I have flushed every once in a while when I take Simvastatin. Eating seem to trigger the flushing after I have taken both of those meds. Can you get the meds to help the DOA fight histaimine intolerance over the counter? Should I go back to the Allergie Clinic or talk to my PCP about what is in this article..I am thinking that I am on the right track after reading this information.

Leatha, I’m unsure about those particular drugs and a histamine response. An allergy clinic would probably be your best bet for more information, but I’m just not sure. DAO is available without a prescription, though I haven’t seen it in stores. I order mine from Amazon.

I really would like to take Histamine, but I’m allergic to Gluten, which includes corn… I know Histamine contains some corn, so I’m trying to weigh out my options.
I have a leaky gut.
Do you know how much actual corn is in a single dose?
Any reactions to people allergic to corn, gluten?
Are you familiar with any Histamine Blocker that is gluten/corn free?
ANY advice on this topic would be greatly appreciated.
I’ve been detoxing for 3 months without being able to reintroduce ANY foods, including even ANY FRUIT!
I live on grassed fed, organic, antibiotic free beef, bison, and poultry and select non starchy vegetables.
I’ve lost 45 pounds in 3 months and continue.
I really need help on how to reintroduce foods back into my diet.
Thank you so very much!
Blessing

Histame is a very clean DAO supplement. I can’t remember if it contains corn, but it’s preferred by many people with food sensitivities. Each capsule isn’t as strong as the other supplements, but it has few additives. For your other questions, the manufacturer would be the one to ask.

I did three Skype sessions with an excellent nutritionist when I was in food-related turmoil. Let me know if you want her name and I’ll email it to you.

Oh yes, please give the name and contact information of the nutritionalist! I’m so confused and trying to research all this stuff by myself online!
If you have time, which I’m sure you don’t, I’ll take any information you can provide!
Thank you ever so much!
God Bless You!
Thank you for answering me so promptly also.

Re corn allergy, I am fairly certain that Histame does not contain corn. I am allergic to corn (in fact, I found out twenty years ago that corn was responsible for my migraine headaches). I began taking Histame several months ago and it has changed my life. Incidentally, kind of a neat story as to how I discovered the corn/headache connection. I suffered an extreme immune system “crash” roughly twenty years ago and my Baylor doc sent me to an environmental medicine M.D. He asked me during my first visit whether or not I was an ex-smoker and, when I replied that I was, he suggested that I try avoiding all food and drinks containing corn and corn syrup. He told me that tobacco leaves are cured in corn and that every time you take a drag off a cigarette you are ingesting corn. He then told me that any time you eat a food on a daily basis, you are going to develop a sensitivity to it which explains why ex-smokers tend to drink soft drinks containing corn syrup and eat a lot of corn chips and other corn-containing foods. It’s how we get our corn “fix” after we stop smoking cigarettes. In any case, he was absolutely right. No corn or corn syrup translated to no more headaches…for the first time in decades. I became so sensitive to corn for awhile that I couldn’t even eat protein from corn-fed animals (which can be a challenge). Also, I think that’s the reason that Excedrin was the only product that could stop my headaches. All other pain relief meds, according to my research, contain corn. Excedrin doesn’t.

Wow, Sue who was your doctor? could I have the name please. I have a child with migraine and lots of food allergies and food intolerances and histamine intolerance for sure because DAO helps. I have long heard that we crave foods we are allergic/intolerant to, but I didn’t understand why. Fascinating.

I am a mother of nine children and my children and I have had food intolerances for years. All of my children are intolerant to salicylates, amines, and histamines. Their reactions grew in force, but I could track them to food because I have so many children. Their reactions include migraine headaches (we all got migraines, my 4 year old had debilitating headaches every day since she was an infant), arthritis (my 9 year old had such swelling in her neck that she ended up having a fusion in her neck at C!/C2 with a bone graft from her hip to keep her head upright — it was stuck tilted and to the side), hair loss (my 15 year old lost ALL of her hair and was devastated in high school), brain fog (my children went through numerous and extreme episodes of foggy detachment that made school and relationships difficult), stomache problems (constant ulcers and diahrea), body swelling — not only in joints, but also in feet and legs that would swell huge, back pain that made physical activity or any sports painful, bloody noses, dizziness, and temperature regulation problems. No doctors would ever believe me about the tie to their reactions and food. I know this has to be genetic. All 10 of us suffer together. We were down to 5 foods — plain chicken, plain celery, plain iceburg lettuce, an occasional egg, a little milk. That’s it…otherwise the reactions were immediate and severe. We suffered as a family for years while I explored the food connection. Since then I continued to study enzymes and have found a miracle. I believe that we are genetically unable to produce the DAO enzyme which processes out histamines and chemicals from our food. We started taking the DAO enzyme supplement every time we eat and we can all now eat almost any food. We always take a good comprehensive digestive enzyme with our food and DAO to make sure our food is broken down quickly and completely so that the DAO is still present when the food gets to the small intestines. We used to eat only 5 foods. Now there are only about 5 foods we cannot eat. DAO has changed our life. It is a miracle to change the lives of so many children all at once. Doctors still don’t want to talk about the food connection, but they cannot argue with reaction free proof — no headaches, no swelling, no brain fog, no arthritis, no temperature problems. I am so amazed I just want to share our miracle with other children suffering.

Diane, thank you so much for posting. I have an affected child who is loosing hair too. did it grow back. How much DAO are you taking relative to food intake? We were down to only veggies. no meat, no dairy, no eggs, no soy, no strawberries, eggplant, avocado, no wheat. has hair gown back? Hair may be because your body attempts to put out the histamine “fire” by calling on the adrenals to produce cortisol. (did you ever have any cortisol tests?) and when the brain calls the adrenals using CRH/ACTH response the adrenals respond…with cortisol but also their other hormones DHEA, Andro, etc, all get produced too. And on a relative basis both in an up and down direction DHEA is much more sensitive by at least a factor of 10 to ACTH stimulation.

oh, also, there is a website from Spain called daodeficit.org on one posting and it was a sidebar on the right where it had some blog comments or Q&A and it said that histamine formed crystals on spinal column, and they specified sacral and lumbar. I just about fell over as my child had a spondylosis fracture year ago. I emailed them frantically, but no reply yet. But this makes sense to me in this way…when I thought about it. The tubermamillary nucleus (TMN) in the brain is where our histimingeric neurons are. We also have mast cells which contain histamine in the brain and we know there are some of these guys at the endpoints of the trigmenial nerve. But anyway, in the brain there are ventricles where the cerebral spinal fluid (CSF) is produced, this is right near the TMN. Our body changes out the CSF at least 3x per day. Stuff, toxins and histamine get exported from the brain in the CSF. CSF circulation is VERY SLOW. Takes hours for something to dissipate. CSF circulates all the way down the spinal column. And it must dissipate out through very small capillaries or something…all along the spinal column. People with neuro disorders like MS, Parkinsons and Alzeheimers we know have high histamine in CSF. I bet migraine patients do also, if DAO is helping you. Histamine affects Vitamin D and bone formation. Yes, seriously. (we have about 150ml of CSF but the body makes 500+ml per day, so a fair amount leaks out along the column) I have a friend who’s daughter has migraine and she has a severe neck vertebrae problem too.

Hooray for you! I am known as a universal reactor, after having suffered an immune system “crash” some twenty years ago. I react to foods, chemicals, wifi and cellular phone radiation, just about anything you can name. My body’s preferred way to react to most things is via histamine, causing “hot flashes” to be an almost constant in my life…until I discovered Histame. It has literally changed my life. I find it so very interesting that people’s reactions to histamine can be so varied, from headaches to everything that you and your children experience, to the flushing that I experience…in all cases to have something as simple as a DAO supplement resolve the reactions is astonishing. How can we get this information out to holistically inclined doctors,and to the general public? Any ideas? I’ m going to write a book (one of these days) but would very much like to be able to reach the masses before then (as if I think I will be able to,reach the masses with my book :).

Hello, in reading this information, I am thinking perhaps my Dad and I have Histamine Intolerance. I am wondering if ALL HI sufferers get migraines? We both get headaches, but not Migraines. I have Fibromyalgia and so, of course, a host of other problems. I know I do have histamine problems of some sort. One thing that came up years ago was when I went to get acupuncture done and every needle site had a huge red circle around it on my skin and my muscles cramped up badly. Also, I get raised water blisters in my mouth often when I eat. I have been on many elimination diets and get intermittent reactions to different foods with no rhyme or reason. My Dad always says he feels “wonky” after eating most anything. But it seems like most people responding here can track their reactions through migraines and am just wondering if it may not be HI if I don’t get Migraines. …? Thanks for any response.

It’s very possible to have histamine intolerance without migraines. This site is migraine-focused, which is why so many people have mentioned it. The blisters you get sound a lot like the mouth sores I’ve gotten for most of my life. They went away when I went on the low-histamine diet. Best of luck finding relief.

I have started a cluster headache cycle and this is strongly related to a high histamine release. I have purchased Pycnogenol (natural histamine) and Histamine Block (DAO supplement). Do you know anything about the uses of these two together?

Are you on any headache preventative medications?
I have histamine intolerance symptoms that manifest as daily pressure headaches. Triptan medications are helpful, Benadryl is helpful and I haven’t taken the DAO enzyme enough to know how helpful it is I’m about to start the low histamine diet this week and I’m just wondering if any preventatives are helpful along with that
Thanks
Lisa

i took daosin for a few weeks once a day for migraine type fortification spectra i had no head ache but visual disturbances for 5 years 24/7 i did try my gp and had no response to any treatment , i read up on the visual disturbance and decide it might be migraine with out the head ache,i had high blood pressure diagnosed and was treated and it was under control. for three years this had no effect on the visual disturbance , daosin seemed to get rid of the visuals but it made my bp go malignant and has been uncontrollable since taking it .histamine is a vasodialator i assume that knocking it out has caused a vaso constriction .i can drink red wine and eat a limited amount of cheese again but would rather has normal bp

It’s amazing to see how many people sharing their experiences here on one of the most complex I have been trying to solve for the past 8 years.
Question to people who have benefitted from DAO, have you stopped taking migraine prevention medications e.g. divalproex? I would really like to get off my medication if I can, since I sort of know what tyramine foods to avoid, and have been recently trying my luck with a DAO supplement.

Simone, DAO degrades histamine in the digestive tract, so I don’t think it could help with pollen. Quercetin might be helpful. It’s a plant-derived antihistamine. I don’t use it, but know many people who swear by it.

Hello,
The supplements you name are made from extract of pig kidney, if I understand correctly. Since I am vegetarian it is not an option for me. Do you know of anny other products that are not made from animal source?

I RECENTLY TRIED VINPOCETINE 5MG A DAY NO PRESCRIPTION REQUIRED
IT ENDED ALL THE FORTIFICATION SPECTRA WITHIN 15 MIN , I UNDERSTAND IT ACTS LIKE VIAGRA FOR THE BRAIN, IT IS A VA SO-DILATOR . I DID TRY 10MG 3X PER DAY AS PER PACKET AND IT INCREASED MY BLOOD PRESSURE , SO REDUCED THE DOSE .
WOULD SUGGEST YOU START AT 5MG/DAY AS A SNGLE DOSE .

I have a question on dosage of DAO. I am currently taking DAO Histaminase – 1 capsule = 5000 HDU. I commonly see 20,000 units as being the recommended amount. Is that per day or per meal? I have been doubling the dosage on these pills, taking 10,000 units/meal, but not getting relief of my symptoms (both G.I. and migraine) yet – it has been 1 week. Am I not taking enough or do I need to wait longer to see results?

Polly, I take one capsule for every 400 calories I eat and take them about 10 minutes before each meal. The enzyme doesn’t build up in your body (it’s flushed out after a few hours), so it’s unlikely that you need to wait longer to see results. You might need a higher dose than you’re taking or need more (or less) time between taking the capsules and eating.

I wanted to make a general comment for contemplation. So I have some mild kind of DAO enzyme loss of function. I am fine most of the time, but if I got a high histamine red wine sometimes 2 sips and I could be in agony for 3 days. However, I didn’t really have many problems except for wine (I am almost 50). I had colic. I have a child who has severe histamine intolerance, daily chronic migraine, oral allergy syndrome (cross reaction with birch pollen) and food intolerance which is probably all histamine. For her crazy, accelerating symptoms. OK food list became really short. She was born in 1999. Possible she has 2 defective DAO genes and I have one, but my husband has zero histamine intolerance symptoms, zero. Migraine is on the increase. Cyclic Vomiting Syndrome on the increase which is also histamine. ADHD is associated with low DAO. Many things related to histamine. I cannot shake the idea that this is related to Glyphosate in the food supply. We had Roundup being sprayed in the 80’s, but in 1999 it went off patent and the usage went exponential. Professor Stephanie Seneff from MIT has published a website with correlations to usage of glyphosate and incidence of diseases which are far ranging. We know it is an endocrine disruptor. Where I think this is related to DAO and histamine is our microbiota. So Glyphosate we are told by Monsanto acts in plants on the shakimine (spelling?) pathway, and enzyme pathway which does not exist in mammals. But Seneff points out that pathway exists in our microbiota, which have more cells in our bodies than our own cells. She believes it kills off the good bacteria and alters the balance. Gut inflammation will lead to low DAO. You can’t wash it off the food. It is absorbed systemically. In 2013 the FDA INCREASED the acceptable levels of glyphosate residue in foods. Oh, and now we have so many glyphosate resistant weeds (superweeds), that now they are making GMO seeds resistant to more than one herbicide, latest one dicamba (a component of agent orange). When will we learn?
So maybe the younger kids never had a shot of their gut bacteria developing normally. Due to constant glyphosate infusion in the food supply. Corn, soy, sugar beets, canola, are all GMO crops. But they spray it on non-gmo crops also at the end of the season to kill and dry the plants for harvest, especially legumes and grains. Eat organic.

HI Michelle, There are multiple ways that histamine and other vaso-active amines can cause problems. One is not enough enzyme for a normal diet, one is excess production of histamine by our body, whether it be allergies or mast cell disorder, and there is also the gut flora to consider. Some species of bacteria (putrefactive bacteria) can turn the amino acid histidine that is found in many protein rich food, into histamine. So whilst a person can have a normal amount of enzyme, if you are overloaded with histamine or other diamines that use this enzyme you will not be able to handle it. Most people are able to produce lots of diamine oxidase in the gut to deal with amines like histamine before they enter the body. Some like me, have a limited capacity to do so and thus I have really struggled over the last three years due to histamine overload. My ability to deal with amines has changed in about four punctuated points during my life. When I was young, I had loads of anti-biotics due to ear infections, when I was older I did not look after my body when I was at uni, and then after my second daughter was born and I was again on antibiotics, and then three years ago I had a weird infection that started as little blisters on the inside of my lips, then to my mouth, tongue, then down my throat, it was not thought to be hand, foot and mouth. Two weeks later my food intolerance went through the roof. I used to only have difficulty with high amine food, but suddenly I started getting all the same symptoms I would get from histamine overload, but from eating low amine proteins (fresh meat), only it would not happen instantly, there was a delay ranging from about 4-12 hours (my digestive system sometimes moves like a slug, which makes the problem worse). I eventually had my stool tested and indeed I did have strains of bacteria that can produce biogenic amines such as histamine. What to do about it is harder. My naturopath gave me lactulose which favours other types of bacteria, although I have stopped it after a few goes as I was not feeling well, and ecologically this does not seem the answer to me. As putting a high nutrient load into the gut could just cause me to switch between problems with one bacteria for another set. (Nutrient overload in ecosystems usually decreases species diversity, and increases populations of a few opportunistic species. Species diversity is linked to gut health, high is good). Anyway, I have rambled a bit. My point is to understand the role of your gut microbiota in contributing to this issue, as well as other factors such as genetics and external influences. I am very much in favour of healing the gut rather than eliminating. GAPS focusses on this, as does Healing Histamine website. Eating a wide range of vegetables, including plenty of leafy greans and high fibre foods like legumes should encourage a better range of bacteria. Chewing food carefully to make sure you digest your protein rather than leave some undigested for the bacteria to turn into histamine may also help. Also suggest you get your child’s stool checked by dna analysis – make sure the testing kit has some sort of fixative. Good luck, very very tough for a parent and young one to deal with. 🙂

I would go to Seeking Health website. They sell a supplement called Histamine Block. It may have a small amount of corn, but I think it’s the proteins in corn that can cause reactions in people who have a corn allergy. I believe the acetylated corn starch it contains shouldn’t be a problem. I personally do not do well with corn YET I can take this supplement with no problem. It’s expensive, but you can sign up for their membership and get 10% off. It’s worth it in the long run for me because I must take these with almost every single meal. It has changed my life. Histame didn’t do enough for me (when it was available on iHerb and other sites). It just wasn’t powerful enough because it didn’t have enough DAO in each capsule. I would end up taking 6 at a time to feel a difference. With Histamine Block, I take 2 and I don’t feel a thing, no hangover feeling, no migraines, etc.

Sharon, not that I know of. I take cyproheptadine, an prescription antihistamine of the same era. I had trouble with drowsiness for only the first couple weeks before my body adjusted and the drowsiness stopped. I also use it as a preventive treatment (taking it only once a day) rather than an acute treatment when symptoms flare after meals. When I first started taking it, I took it at 6:30 p.m. so I could sleep off the side effects. Benadryl might work the same way. If not (and you have a doctor) cyproheptadine is a cheap prescription medication.

Sharon you can try one of the motion sickness meds, like Dramamine . There are different brands but they are an H1 antihistamine with an added stimulant so it does not make you toooo sleepy. Try low dose first to see how the stimulant part goes if you are sensitive to caffeine or stimulants.

From what I understand any H1 antihistamine which crosses the blood brain barrier will cause drowsiness. The newer ones like Zyrtec do not cause drowsiness because they do NOT cross the BBB. The histamingeric neurons in the tubamamillary nucleus control the sleep wake cycle along with a myriad of other things, blocking those receptors is what makes one sleepy, until the body adjusts. Interestingly, the placenta makes an increasing amount of DAO during pregnancy- it escalates through first trimester and then levels off at between 500-1000 times normal non-pregnant levels – this is what makes women so sleepy during first trimester lower levels of histamine.

Hi, Thanks for your comments.
I am in between buying more DAO. I’m trying Benadryl, B-6 and VIT C.
Something went wrong yesterday and I am now under a migraine. If I take the Benadryl again now will it help my migraine? It’s so draining trying to figure all of this out. I’m growing lentil sprouts too, they will be ready the first week of Nov. I guess the best way to go about this is to do a daily dosage of DAO.. AND Benadryl? I am changing my diet but there are still food and drinks that I’m not sure of. The migraines, once they set in, are three day events. I’m hoping to curtail this one. I don’t want to be under the weather this weekend.
Thanks for any suggestions.

Sharon, Benadryl might provide some relief it you take it now. Hospitals often give it when patients go to the ER to break a migraine attack. Antiemetics (like Compazine or Reglan) also provide pain relief for some people and are commonly used in the ER. Best wishes it lifts soon.

Oh, forgot one other thing to try w active migraine, alkaseltzer gold or regular alkaseltzer. There are sodium potassium pumps on neurons which facilitate the charge potential on their membrane. Electrolyte imbalance can cause them to become stuck, and neurons do not fire. Gold has potassium and sodium, regular has sodium bicarbonate and aspirin. If you do gold maybe take aspirin to block the prostaglandin D2.

Hi, sorry you are being visited by the beast. Antihistamines do not help my daughter, but Elavil did, she did not like side effects. Some other ideas for you, if you have not done 23andme do it if you can. I learned a lot about methylation status, CBS mutations which can give you tendency toward mast cell activation, you can determine if you are genetically low DAO and find out status on other histamine related enzymes like MAO and HNMT what you have going on. Different supplements would possibly help different things. Another thing I learned recently mast cells are part of Th2 immune system, the two halves of your immune system Th1 and Th2 ideally should be in balance. If you have a lot of histamine issues mast cells are likely over active and you may have Th2 dominance, if you have many food intolerances and allergies by focusing on gut health you can help it. Clostridium bacteria make butyrate a shirt chain fatty acid. It feeds the epithelial cells of the colon and the mucin cells that make the mucous barrier – essential for tight junctions. Get some sodium or sodium/potassium butyrate capsules (smell bad) and take it 3-4x a day, 2-3 caps. Butyrate also increases the gut production of Tregs, regulatory T cells which “teach” your immune system tolerance of food proteins, and it increases the secretion of IL-22 which is antiinflammatory. I have also read it kills h.pylori but not sure. Maitake mushroom d fraction also boosts macrophages which are Th1, improving balance. Also on Amazon google clostridium butyrate (this is probiotic which produces butyrate), there is a Japanese product which is like Mira-something. Also Align is good, no histamine generated. And also I read, aspirin blocks creation of prostaglandin D2 which is implicated in the migraine process. Try Epsom salt bath or foot bath when you have migraine active, has to be magnesium sulfate. Google mast cell master and you will get professor at Tufts, lots of research. He has product neuroprotekt. Do not add more than one supplement at a time. The butyrate takes several months to make a dent in dysfunctional gut. But I have a friend who suffered Colitis 10 years. 18 months on butyrate, completely clean colonoscopy. Zero inflammation. Gastro was shocked. After 2 months we were able to tolerate 2-3 foods again that had been eliminated. She was basically vegan and certain veggies and fruits were issues. Good luck.

Migraine sufferer: I grate ginger into my food when I have migraine with associated visual disturbance. about 1 inch, finely grated. Or I juice it with a cold press juicer. It clears up my visual disturbance in about 10 minutes and I have hardly any pain. It may help your migraine. Have you also tried turmeric? Benedryl has additives in it that may not be great for you with food intolerance issues. Also there are 4 Histamine receptors and most anti-histamines focus on H1 receptor. I am not aware of any that affect H3 and 4 receptors. If your migraine is due to histamine and H3/4 receptors then the benedryl will not have an impact. That is where reducing histamine consumption, increasing foods with anti-inflammatory properties, taking DAO supplements come in. Be aware that overgrowth of putrefactive bacteria can also increase histamine intake too. Eating food that releases histamine can also, and combined with that some people have a mast cell disorder. Make sure you have enough of the precursors for dealing with Histamine in your body too – once required for your methylation pathways – the fact that you are taking B6 and Vit c suggests to me you have already looked at this. Good luck 🙂

Sarah.Thanks for your info. Yes I recently discovered that Benedryl is not helping. I’ve tried ginger in the past but probably didn’t take enough. I think I read Terumric was a histamine activator. I believe you are right about a mast cell disorder. My DAO order won’t be in until November 3rd.
I’m so glad to find this discussion site. It makes me not feel so crazy and hopeless and alone. Thank you!

Just now, out of desperation, and the fact that my “fresh” ginger in the fridge was all shriveled,
I went into my spice cabinet and found the ground ginger for baking. I scooped out a little less than a quarter teaspoon and swallowed in with water. That was 40 mins ago. I can’t say that my headache is completely gone but it does seem much better, like it’s not in complete control! Sulfur Dioxide is the other ingredient, if that proves to be a problem then there could be some backlash… 🙂

Ouch, horrible to feel like that – but know how you feel. I have not tried it with dried ginger. I do not react to turmeric capsules, and I am pretty sensitive. But that said reactions can be different for everyone. I also don’t avoid all histamine activators if they have other benefits. Have a look at the Healing with Histamine site, as her process of eating for max nutrition instead of withdrawing all histamine food is a good one. As for the DAO – I am pretty sensitive and I do not have 100% success with it, and it gets pretty expensive when you use a lot. 🙂

Hi. I’ve been trying different things over the past couple of weeks. I must say I’m not a fan nor do I think I could function through two weeks if that’s how long it takes to NOT feel drowsy when needing to take Benadryl. It did work for me once, but I’ll need to save that one for night time only.

I did finally get a DAO Blocker, using sparingly.

The suggestion for fresh ginger on food ( I made a mighty strong cuppa with it ) worked magically on an in-coming headache/migraine late one evening. I was dreading the next morning but awoke without incident! YEY. Thank you!

How often does one take the histamine block? In other words how long do it stay in your system? For example if I go to a dinner party…take 1 His block before wine and cheese and dinner is served an hour later that also has his releasing food do I take another?

Mary, I’ve heard three hours, but you may want to test it out for yourself. Digestive enzymes are not systemic and only stay in your body through the digestive process. People digest at different rates, so what works for one person may not work for you.

A good question. I had been wondering that myself. I’ve read to take the Blocker 15 to 20 mins before the offending food or drink is ingested. I’m a slow digester, so probably wouldn’t need another pill for several hours.
Good to know.
Thanks!

I suspect that it would depend on how much DAO your own body produces, how much histamine you are ingesting in your food, also how much histamine is being produced by putrefactive bacteria in your gut flora, and of course the person’s gut motility. These factors would all affect how much you need and how quickly it is used up, and how quickly it hangs around. Normal healthy people produce DAO into the gut lumen, so I suspect us histamine intolerant people would have varying degrees of DAO being produced, and what suits one, may not be enough for another. So trial and error is most likely the way to go. You may also want to consider taking some quercetin before meals too, which is supposed to reduce mast cell release of histamine. I have not done enough research into this to know how effective it is. Has anyone else tried it? 🙂

DAO enzyme. It primarily degrades histamine. However in doing some research and in talking to a friend who is a PhD chemist, and he did research DAO degrades histamines and diamines and monamines. Tyramine is one of the latter two. So it degrades tyramine also, although it may have preference for histamine. Frequently foods high in one are also high in the other. Just thought tyramine sensitive people might want to know DAO might help them too.

Our 3 year old is suffering badly from Zyrtec withdrawal, and probably she does indeed have high sensitivity and intolerance to histamine, but i suspect it was resulted by usage of the zyrtec. anyhow, quercetin & Vc helps a bit while we trying to get her rid of the zyrtec, but not enough, rashes and hives quite hard to battle pls quercetin can be bad for iron absorption if used for long. hence more search led to this DAO enzyme, does anyone here know what’s the right dosage for a 3 year old?? many thanks!!

Hi all! I am really reaping up the mass information that everyone is sharing. I also suffer from migraines and I’m beginning to think it’s HI. One of my many triggers is when I get hot or overheated from exercise, running around doing house work or even just a day at the beach from the hot sun. Is there any way this is connected to histamine intolerance? Thanks for all your stories!

You are spot on! I too have been wondering about this. Finally got to the bottom of it. I wrote to a company, Allergy Research Group LLC/NutriCology, 800-545-9960 ext. 125,
that I had been ordering from.

Here are my emails from them that told me what was going on. I still don’t know what I’m going to do when I run out. There is a company that has the ‘corner on the market’.
I don’t know if one can order w/o becoming their patient!

Hi,

Would like to get to the bottom of why this product is so difficult to find on many of the varied Vitamin and Mineral sites?

I have been ordering from you but would like to know what is going on with these other companies because I have had orders go through and then wait forever only to hear that they no longer carry the product.

Anything you can shed light on?

Thanks,
Sharon Kime

These emails are from Allergy Research Group LLC/NutriCology that I have been ordering from. They told me what was going on:

Dear Sharon,

At this point in time, there is only one company that can sell DAO, they have the exclusive on the raw material for now, but that may change in the future. They are Xymogen and the product name is HistDAO.

to me
For now, that is correct. However that may change in the future.

Diane

From: Sharon Kime [mailto:sharonkime@gmail.com]
to Diane
THANK YOU!

to Diane
Ok, I get it now…and it does sound like this company wants to capitalize on the Histimine Block. They won’t even tell you how much it cost w/o going through other channels. Really sad.
​Thanks for the info. Please keep me informed as to when your co. might be carrying it again.

Ok. I’ve grown my sprouts and they’re ready to blend with something and drink.
I understand that 1 cup is what I should use. What I’m not clear on is WHEN. the timing of consumption. If I’m going to go out and have some wine (example) or if I’m about to eat one of the offending foods, when should I have had the sprouts? And, can one make and take the sprout containing smoothie with them if wine of dinner is going to be delayed? What is the shelf life?
Thanks, if you can help me answer these questions!

Hi i was wondering if anyone has suffered from diarrhea from dao supplement. I bought it from a company called Umbrellex. Took my first dose and ive had diarrhea since ): any help would be much appreciated.

Hi. I didn’t have that problem. Bought from NutriCology. However I gave up trying to buy online as it’s been to difficult to find. I have been , and with much success, growing​ legume sprouts .Getting DAO in this form has worked for me!
Also, I have found that I have had a Magnesium deficiency even tho I have been taking a supplement it apparently needed to be a higher dose. Now this did give me diarrhea until I lower the dose a little. Vit C will do the same thing. Are you taking those things as well?
To add to that I have read that too much estrogen can lead to migraines. I don’t do any soy but have been on hormone replacement, bio identical, for several years, and yes, my migraines started the same time I began the estrogen, progesterone, etc.

I have been taking atarax and cetrizine for excessive histamine production. This was prescribed by the doctor a yr ago. I used to get red swollen itchy hot bumps all over my body. They stopped like a miracle after the medication.this only lasted for ayr. The bumps have returned even though I am on the same medication still. I never stopped the meds. What now? Wanted to try the DAO SUPPLEMENT from Holland and Barrett. Are those any good? Can I still continue with my antihistamine meds along with talking DAO suppleness?

Regarding the “Histamine Block” product. The makers specify that it contains carboxymethylcellulose . I think that potential purchasers should be made aware that this compound is implicated in exacerbating or even causing Ulcerative Colititis. This is a very serious and lifelong disease.
See http://www.latimes.com/science/sciencenow/la-sci-sn-metabolic-bowel-emulsifiers-20150225-story.html
For some, the cause of histamine overload or DAO deficiency is the GI bleeding caused by Ulcerative Colitis. For these people especially, it is important to highlight that “Histamine Block” contains this.